Combining a solid object Fresnel glow on top of a glass object?
You can do this by assigning faces materials in edit mode.

Here's how:

1) Enter edit mode in Blender.

2) Select the top face you want to be able to apply the "purple" shader to.

3) Make sure your material colors are already created. You will need at least two separate materials. (One for the top face, and one for the rest of the cube).

4) Go to the materials tab, and select "Assign". This will assign the material to the single face.

5) To prevent the material from being applied to the entire object, press CTRL+I to select inverse.

6) Assign the previous material to those faces the same way you assigned the other material.

Last) View it in render, it should look awesome.

Here's a picture of multiple assigned materials on one object:



The answer in total, to this question is simple. If you know how to assign materials to individual faces of an object, then you have solved the problem.